The invention is related to the technical sector of connection equipment for plumbing and the distribution of fluids (water, gas, and other like fluids) and more particularly to valves which are intended to permit the flow or stoppage of fluid in circulation.
The use of valves which are fabricated of thermoplastic materials is known.
These valves are represented for example and not by way of limitation, in FIG. 1. They include a body (1) having on an axial level, opposing nozzles (2) permitting the adaptation and joining of pipes. Inside, the body is equipped with a closure element of the valve type (3) or gate valve controlled in its position by a maneuvering means (4) of the faucet or other type. The entirety of the valve body may or may not be fabricated as an integral unit, or welded with end fittings.
This type of product is widely used, offering all assurances of reliability and safety.
This type of product is intended to be buried and normally its use is anticipated for a very long service life of between thirty and fifty years.
This type of material may necessitate the use of a flushing element in the form of a tube (5) likewise of thermoplastic material connected and attached perpendicularly to the body of the valve, said tube being also connected to an opening or conduit (1b) disposed in the walls of the body and emptying inside the latter to permit purging the air.
The problem posed resides in the fact that the tubular element (5) constituting the purging means is attached directly by soldering or welding (7) onto the valve body. It turns out in practice that during qualification tests (aging, bending, etc.) conducted on the valves and in accordance with established standards, it occurs relatively frequently that the soldering comes loose as a result of the propagation of mechanical stress appearing in the material of the valve body. This situation is particularly annoying for it entails the total loss of the valve, which deteriorates and becomes unusable.